The bacreriocidal activity of common disinfectants on glucose non-fermenting Gram negative rods (non-F GNRs) were tested. Some strains, especially those of Pseudomonas cepacia and Alcaligenes feacails, were markedly resistant to chlorhexidine digluconante (Hibitane^○_R) and cresol soap at commonly used concentration. Blood and NaClinhibited the bacteriocidal activity of Hibitane and benzalconium chloride (Osvan^○_R). The activity of Osvan was more dependent on temperature than Hibitane.